European document EP 1 009 005 B1 describes a control device of a circuit breaker opening or closing electromagnet, said device featuring local and remote control capability. The device includes two power supply terminals and a remote control terminal, as well as a local control terminal. In a first control mode, two power supply terminals are connected to a voltage supply source via a first local control means. In a second control mode, the two power supply terminals are connected directly to the voltage supply source, and the local control terminal is connected via a second local control means to one of the power supply terminals. Also provided is a communication module. Presence detection means are connected to at least one presence detection terminal and designed to automatically detect connection of the communication module to the remote control and presence detection terminals of the device. Opening and closing of the circuit breaker is controlled either by the second local control means or by a control command from the communication module. The device further includes means for comparing a quantity representative of the voltage applied to the power supply terminals with a preset threshold, means for detecting the presence of a communication module at the remote control and presence detection terminals, means for commanding excitation of at least one coil of the electromagnet when said quantity is greater than said threshold. The excitation of the coil is effected either automatically in the absence of detection of presence of a communication module, or, when said presence is detected, if a control signal is, in addition, applied to the remote control terminal or to the local control terminal. Further, a resistive voltage divider is connected to the power supply terminals for interconnection of a rectifier and a microprocessor-based circuit. The microprocessor-based circuit includes means for comparing, detecting presence and commanding. The local control terminal, which can be controlled by the local control means, is also connected to the microprocessor-based circuit. A transistor is connected to the output side of the microprocessor-based circuit as an electronic interrupter, the coil being connected to the drain side of the transistor.
Thus, according to EP 1 009 005 B1, several terminals are needed to be able to implement the different control modes for the circuit breaker. In particular, a communication module is provided here which serves to operate the device in a local mode and/or in a remote control mode. In purely local mode, in addition to the one local control means, a second local control means is provided in the region of the one power supply terminal, which makes the device quite complex in terms of design.